Golden ratio guide

Start

The tool opens on the Fibonacci spiral, drawing itself one square at a time on a dark grid.

What you need

• A current browser. It draws on a plain canvas, so no WebGL or GPU is needed.
• A photo, only if you want to lay a composition grid over it.

Your first result

1. Open Golden ratio. The spiral is already building.
2. Under Mode, pick one of the five drawings. Under Parameters, move its one slider: depth, points, subdivisions or seeds.
3. Tap or click the canvas to move the centre there. The drawing starts again from that point.
4. To zoom, scroll with a mouse wheel or pinch with two fingers. Two fingers also move the view.
5. Press Save PNG at the top of the panel to keep it as golden-ratio.png, or Copy image to put it on the clipboard.

Good to know

• Turn off Auto-animate to see the whole drawing at once instead of watching it build.
• A press that moves more than a few pixels is not a tap, so it leaves the centre where it is.
• The PNG is the canvas as you see it, at the size of the frame times your screen's pixel density. Every pixel is filled: where nothing is drawn, the frame's near-black shows, so no part of it is see-through.
• Every picture here is standard range (SDR); none is HDR.
• A photo is kept on this device, and every lab tool that takes a picture opens with it, until you press × on its tile. Here it opens under the drawing.
• On a phone the controls sit in a bar at the bottom of the screen. Tap the bar to open them.